Evidence for an ancient impact basin in Daedalia Planum, Mars

Publisher Website
Google Scholar
Abstract
Geologic mapping has provided observations that some features on Mars are morphologically similar to lunar Imbrium Sculpture materials. These grooved features occur in clustered sets of a dozen or more, are spaced 1 to 10 km apart, and are unlike other linear Martian features such as yardangs, faults, ancient valley networks, and mass‐wasting features. We propose that they represent impact materials from an ancient basin. The orientations of these features were plotted as lines on a Schmidt net, and the density of the resulting intersections suggests a likely source area at approximately −26.0°, 125.0°, or roughly the center of Daedalia Planum. Numerous features, geologic materials, and Earth‐based radar data indicate that a basin with a diameter of approximately 4500 km with an early Noachian age is centered at this location. Four interior rings with diameters of 1100, 1500, 2200, and 3200 km and an exterior ring with a diameter of approximately 6400 km were found. The rings are spaced with a ratio of , which is similar to the basin ring spacing on the other terrestrial planets. Both concentric and, infrequently, radial basin‐related faults were recognized, including Claritas Fossae, Gordii Dorsum, and the Thaumasia graben. Faults or zones of weakness related to the basin rings may have influenced the position of the Mangala Valles source area and Arsia Mons. Based on the location and morphology of early Hesperian to early Amazonian volcanics composing Daedalia Planum, the Daedalia basin may also have extensive, deep‐seated interior faults capable of extruding mare materials to the surface.